Search

Trim-loss problems or cutting stock problems involves solutions to the cutting of product paper rolls from raw paper rolls and the minimization of costs for over production. Trim loss problems associated with the paper industry in a Finnish paper converting firm are presented to explain the dissimilarities in numerical solutions. Results reveal that while the problem can be converted from linear to convex forms and be solved either as mixed-integer or convex-mixed integer non linear programming models, numerical efficiency solutions differ according to transformation.

This paper presents structural optimization of piezoelectric modal sensors and actuators for plate structures. Unlike for beam structures, the design of constant thickness, distributed modal transducers for plate structures is not straightforward. In this work the design problem for plate structures is tackled as a (multi-material) structural optimization problem where the optimal distribution of the piezoelectric material as well as its polarization profile have to be found. For the solution a parametric level set method is proposed. This allows simultaneous shape and topology optimization. In contrast to most conventional level set approaches we choose a parametric level set method that does not involve the direct solution of the Hamilton–Jacobi equation using numerical methods such as the finite difference method. The optimization problem is directly posed in terms of the parameters of the parameterization and is solved with an evolutionary algorithm. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Angiogenesis is required for successful implantation of the invading blastocyst. Vascular endothelial growth factor (VEGF) is an important key player in angiogenesis and vascular remodeling during the implantation process. Besides its well-characterized receptors VEGFR1 and VEGFR2, neuropilin-1 (NRP-1) has been shown to play an additional role in the signaling process of angiogenesis in human endometrium during the menstrual cycle, as a co-receptor of VEGF. These findings led to the hypothesis that NRP-1 might play a role in the vascular remodeling process during embryo implantation and the establishment of a pregnancy. Study design: NRP-1 mRNA transcript and protein expression were investigated in human choriocarcinoma cell lines (JEG-3, Jar and BeWo) aiming to evaluate the expression of NRP-1 in vitro, as well as in human decidua of all three trimesters of pregnancy, by western blot analysis (three samples of each trimester of pregnancy). The localization of NRP-1 in human decidua of all three trimesters of pregnancy was analyzed by immunohistochemistry (five samples of each trimester of pregnancy). Results: NRP-1 transcript and protein were expressed in all cell lines examined. Corresponding to the analysis of human tissue by western blot and the localization by immunohistochemistry, NRP-1 protein higher expressed in samples of early pregnancy in comparison to the end of pregnancy. NRP-1 was expressed in the decidua, villi and invading cytotrophoblast of all samples investigated. Conclusions: This is the first study clearly showing the expression of NRP-1 in human decidua and trophoblast, suggesting an important role for the VEGF co-receptor NRP-1 besides the established receptor VEGFR2 at the embryo–maternal interface during embryonic implantation and placentation. [Copyright &y& Elsevier]

Spinal epidural arteriovenous fistulas (SEAVFs) are rare lesions with a low risk of hemorrhage. Most patients with lumbosacral SEAVFs with hemorrhagic events will develop a spinal epidural hematoma from epidural venous pouches. To the best of our knowledge, we have reported the first case of a lumbosacral SEAVF presenting with remote intramedullary hemorrhage in the conus medullaris. A 56-year-old man presented with sudden-onset severe paraparesis and bowel/bladder dysfunction. Magnetic resonance imaging of the thoracic and lumbosacral spine showed acute intramedullary hemorrhage in the conus medullaris surrounded by spinal cord congestion extending to T8, with perimedullary flow voids along the ventral and dorsal cord surfaces. Magnetic resonance angiography and spinal angiography confirmed the presence of a SEAVF with a large lumbosacral epidural venous lake supplied by dorsal somatic branches of bilateral L4 segmental arteries. Initially, the intradural venous drainage had been misinterpreted as a single route. The patient underwent surgical interruption of the dilated intradural draining vein after embolization of the feeding vessels. Another small intradural venous drainage route was found on the follow-up angiogram. The second operation with occlusion of the initial part of the epidural venous lake was sufficient to cure this lesion. With the significant improvement of our patient after treatment of the SEAVF, we speculated that the intramedullary hemorrhage, which had occurred in the area of spinal cord edema, might have resulted from severe venous hypertension, rather than hemorrhagic infarction of the spinal cord. Careful evaluation of the angioarchitecture of SEAVFs is imperative to determine the most effective treatment modality. [ABSTRACT FROM AUTHOR]

Multidrug resistance (MDR) is a phenomenon that is often associated with decreased intracellular drug accumulation in the tumor cells of a patient, resulting from enhanced drug efflux. It is often related to the overexpression of P-glycoprotein (Pgp) on the surface of tumor cells, thereby reducing drug cytotoxicity. In this study, curcumin was tested for its potential ability to modulate the expression and function of Pgp in the multidrug-resistant human cervical carcinoma cell line KB-V1. Western blot analysis and reverse transcription–polymerase chain reaction (RT–PCR) showed that treatment with 1, 5, and 10 μM curcumin for up to 72 hr was able to significantly lower Pgp expression in KB-V1 cells. Curcumin (1–10 μM) decreased Pgp expression in a concentration-dependent manner and was also found to have the same effect on MDR1 mRNA levels. The effect of curcumin on Pgp function was demonstrated by rhodamine 123 (Rh123) accumulation and efflux in Pgp-expressing KB-V1 cells. Curcumin increased Rh123 accumulation in a concentration-dependent manner (1–55 μM) and inhibited the efflux of Rh123 from these cells, but did not affect the efflux of Rh123 from the wild-type drug-sensitive KB-3-1 cells. Treatment of drug-resistant KB-V1 cells with curcumin increased their sensitivity to vinblastine, which was consistent with an increased intracellular accumulation of Rh123. In addition, curcumin inhibited verapamil-stimulated ATPase activity and the photoaffinity labeling of Pgp with the prazosin analog [125I]iodoarylazidoprazosin in a concentration-dependent manner, demonstrating that curcumin interacts directly with the transporter. Thus, curcumin seems to be able to modulate the in vitro expression and function of Pgp in multidrug-resistant human KB-V1 cells. In summary, this study describes the duel modulation of MDR1 expression and Pgp function by the phytochemical curcumin, which may be an attractive new agent for the chemosensitization of cancer cells. [Copyright &y& Elsevier]